Arsenault declined to reveal his sexual orientation but admits it's unlikely he will have a family of his own.

"I think my whole life, since I was 10, I knew that I would be doing something like this," said Arsenault. "I never saw myself getting married. I am a free spirit, independent."

Who wouldn't want his sperm? He is drug- and alcohol-free and boasts that he was raised in a religious family. He is into sustainable energy, bird-watching and sports and even plays the piano and drums.

In fact, Arsenault has made 328 semen donations to 50 women, mostly lesbians in the San Francisco area. They are grateful that he doesn't charge and dispenses with anonymity.

Arsenault is part of a do-it-yourself fertility movement that caters to couples and single women who say they cannot afford the high cost of sperm banks. They also want their children to know their biological father.

Three Google sites, at least six Yahoo Groups and a dozen more fee-based web sites cater to those looking for free sperm donors, according to a recent article in Newsweek. Most are in the United Kingdom, Canada, and Australia.

Arsenault is strict about his donation schedule -- only once in 24 hours. "I don't want to overwhelm myself," he said.

Fifteen minutes before the "hand-over," Arsenault gets a text message from the prospective mother and downs a vitamin-rich slushy made of blueberries, kiwis and flax seed. Then he ejaculates into a sterile cup, one of 200 a year he buys for $50 online from Amazon.

"I really have it down to a science," said Arsenault, who works in high-tech in Silicon Valley. "I am a multi-tasker. "Everything in my life lined up for this."

Women typically do the artificial insemination right afterwards, at a local hotel or in a camper or even a public bathroom, filling a latex cup with the fresh semen and placing it on their cervix.